Gyratory crusher



Aug. '11, 1936.- ,J A MCC/SHELLl 2,050,718

GYRATORY CRUSHER4 Filed April 16, 19354 s sheets-sheet 1l Patented Aug. 11, 1936 PATENT oFFicEf 2,050,718 GYaA'roaY' caUsnEa Jasper A. McCaskell, Glenwood, N. Mex., asslgnoiI to William M. McCaskell, Glenwood, N. Mex.

Application April 16, 1935, serial No. 16,538

15 Claims.

This invention relates to improvements in gyratory crushers and is more particularly a development of the apparatus shown in my prior Patent No. 1,936,728, issued on November 28, 1933.

The principal object of my present invention is to provide a linkage for operating the muller shaft of a gyratory crusher so that under normal conditions the muller will exert a more nearly positive crushing force on materials handled, and when an obstruction is encountered, the muller will tend to crush the obstacle and then afteran interval, if crushing is too difficult, the linkage will move the muller more quickly to a concentric, non-crushing position, thereby being more positive in crushing and more sensitive in subsequent reaction than was possible heretofore.

Another object of my invention is to provide an improved drive for a gyratory crusher having `a weighted eccentric intermediate a crank arm and the muller shaft with the center of gravity of the eccentric so placed that centrifugal forces will tend to hold the mullerin crushing position, but which will tend to move the muller shaft toward a concentric position on a short radius so that, if an obstacle is encountered which the crusher isunable to crush. the non-crushing position is reached more quickly.

A further object of my invention is to increase the crushing efliciency of a muller shaft eccentric drive mechanism for a gyratory crusher by maintaining a ratio between the length of the crank arm and the distance between the crank pin center and the center of gravity of the operating eccentric which is three ormore. while providing for -concentric return of the muller shaft to coincidence with the drive shaft fox` non-crushing relation.

Another and more specific object of my invention is to provide a plurality of eccentrics coacting in a crank pin socket with the end of a muller shaft of a gyratory crusher, such eccentrics having a combined eccentricity such that the muller shaft can be made concentric with the crank socket. while one of the eccentrics is so weighted that it has its center of gravity at 'a point less than one third as far from the center of the crank pin socket as is the center of the crank pin socket drive member.

Another specific object of my invention is to provide a single weighted eccentric for a muller sha-ft drive in which the center of gravity is approximately one third as far from the crank pin socket as is the center of the drive of the crank pin socket so that the center of gravity tends to move on a short arc as compared to the 4an improved adjustment of the elevation of the muller shaft with respect to the crusher laws such thatthe ilneness of grind may be controlled during operation of the machine. I

Other objects and advantages of my invention 10 will appear from the following description thereof, taken in connection with the drawings which illustrate preferred formsl of embodiment of my invention and in which,

Figure l is a central vertical sectional view of 15 the crusher embodying my invention,

Fig. 2 is a horizontal section taken substantially along the line 2-2 of Fig. 1, V

'Fig'. 3 is a partial vertical section taken substantially along the line 3 3 of Fig. 2, 20

Fig. 4 is a horizontal section taken substantially along the line 4--4 of Fig. 3 and showing the normal operating position of the respective elements,

Fig. 5 is a detailed vertical section showing the releasing pin structure,

Fig. 6 isa horizontal section substantially like Fig. 2 but showing the counterweight of the operating eccentric moved into advanced position.

Fig. 'l is a partial vertical section taken along the line 1--1 of Fig. 6 and showing the locking pin locking the eccentrics together,

Fig. 8 is a horizontal section substantially like Fig. 4 showing the muller shaft concentric with the drive shaft,

Figs. 9 and 10 are diagrammatic illustrations of the angular relation of the centers of the respective elements,

Fig. 11 is a horizontal section showing a muller drive having one eccentric with the eccentric in operating conditions, and r Fig. 12 is a horizontal section similar to Fig. 11 but showing the eccentric in collapsed, or concentric position.

In my prior patent, I disclosed a gyratory type crusher for crushing and pulverizing ore and other refractory material in which the muller shaft was driven by a motor through a 'centrifugally controlled eccentric so that when an oversized or overhard piece vof material became lodged between the muller and the crushing jaws, the centrifugally controlled eccentric would vmove the muller shaft center to a new or coneration. The eccentric therefore established a concentric muller shaft center under adverse.

conditions and after the release of the material, the eccentric was subsequently returned to normal operating position by any suitable means.

I n'ow find that in order to get better operating results, a suitable ratio between the length of the crank arm and the distance of the center of gravity of the eccentric from the center of the crank pin should be maintained. The greater this proportion is under practical operating conditions the moreeificient this couple becomes. There is a certain physical relation however, between the center of gravity and the eccentricity of the eccentric due to manufacturing conditions and I nd it desirable to keep the eccentricity as small as possible in order to. maintain a maximum ratio between the length of the crank arm and the distance between the crank pin center and the center of gravity of the eccentric; But in order to make the muller shaft and the drive shaft concentric after the eccentric revolves 180, it is necessary that the eccentricity of the eccentric equal the length of the crank arm and this would normally eliminate any increase in ratio between these two' lengths thus tending to inefilciency in the operation of this couple.l

In my preferred construction, I now provide an additional or auxiliary eccentric which establishes a new crank pin center asfaras the operating eccentric is concerned and the operating eccentric can have an eccentricity substantially less than the length of the crank arm for the desired high ratio, while the total eccentricity of the two eccentrics equals the length of the crank arm for the desired concentric relation of the, muller shaft.

In order to more clearly illustrate the preferred structure I have shown agcomplete gyratory crusher in Fig. 1 which is mounted on a base 8 of a suitable type which may have the driving motor I0 mounted on the top. The motor I 0 drives the drive shaft I2 through a suitable coupling I4 and on the end of the drive shaft and keyed thereto is the crank socket I6 carried in anti-friction relation on the foot bearing I'I by the bearings I9. The crank socket I6 carries an auxiliary eccentric I8 and inside of the auxiliary eccentric I8 is the operating eccentric 26.

The detals of the drive end of the drive shaft are shownv in Fig. 3 in which it will be seen that the operating eccentric 20 is provided with a' vcounterweight 22 which extends substantially entirely around its periphery as shown in Fig. 2. 'Ihe operatingy eccentric is preferably provided with a bearing liner 23 which in `turn carries the muller drive bearing 24 in the end of which is supported the muller shaft 30 as by a -partial spherical bearing`26. The bearing 26 and the liner 23 each facilitate the movement of the muller shaft which is both rotative and oscillatory.

The muller jaws 32 are mounted part way up the muller shaft 2li in a fixed position as shown in Fig. 1, and at a point spaced adjacent the muller jaws 32 lare the fixed crusher jaws 24, such jaws being spaced below the hopper 26 to receive the ore to be crushed. The upper end of themuller shaft 2 6 is `carried on asuitable spherical shaped bearing l! which will beadescribed hereinafter.

The materials to be crushed which are placed in the hopper 36 will pass between the crushing jaws 34 and the muller 32 and being crushed v and pulverized, will drop to the discharge openings 42 in the base 8 as desired. Asthe finely ground material is objectionable in the bearings the foot bearing I1 and other movable parts are covered by a suitable housing 43 which as shown. will prevent the parts from becoming clogged.

The detailed construction of the preferred form of eccentrics is shown in Figs.l 2 to 8 inelusive. Under normal operating conditions, the auxiliary eccentric I8 is locked to -the crank socket I6 to rotate therewith. This is accomplished by a locking pin 44 normally held in locking position as shown in Fig. 3. Preferably the median line of the auxiliary eccentric is in advance of the dead center line through the center of the drive shaft socket and the center of gravity of the eccentric in the direction of f the rotation of the crusher from-15 to 25 or sufcient to make the eccentric have a tendency to tighten against a stop in crank socket I6. This removes the strain from the locking pin when the crusher is operated normally.v course be understood that-a similar result would be had ii' the eccentric were so constructed that its median line lags behind the dead center line fromv 15 to 25. f t

vThe operating eccentric 20 although free to move in the socket of the auxiliary eccentric, is normally held in eccentric relation by centrifugal force, as the crank socket is rotated in the order of 1800 R. P. M. and' the muller shaft is then held firmly in crushing position. If an obstacle is engaged however, the operating ec.- centric will travel a distance equivalent to approximately 45 in advance of the auxiliary eccentric and at that 'point the casing of the counterweight 22 contacts with the release bar 46 shown in Fig. 5.

Engagement of the bar 46 causes movement of the lever 48 to withdraw the locking pin 44 from the crank socket and force it into a suitable recess 20a in the operating eccentric 20. This will thus relieve both eccentrics from thecrank socket I6 and in turn willlock the two eccentrics together. Both eccentrics will then swing together until the operating eccentric 2t)y has traveled approximately an additional 135 or until the muller shaft 30 has become concentric with the drive shaft I2 and then the lock v49 on the crank socket engages a suitable recess I8a on the auxiliary socket so that all operating parts `are locked togetherin a concentric non-crushing position of the muller shaft as shown in Fig. 8'.

A diagrammatic representation of this action of the eccentric is illustrated in Figs. 9 and 10. If the point A is considered the center of the drive shaft and point B to be the equivalent position of a crank pin center, the length of crank arm' is A B.4 If it also be assumed that equivalent length links are used rather than the internal eccentric sockets, the length B E isequivalent to the eccentricity of the auxiliary eccentric and the length E C is equivalent to the eccentricity of the operating eccentric. Under normal operation, the muller shaft, having its center at C will be driven around the drive shaft A as its center It will of with the effective crank arm A B E due to the point. the unlocking of lock 44 and locking of the two eccentrics will cause a combined movement about B as a new center until the muller shaft (point C) has reached the drive shaft center (point A) and is concentric therewith.

The center of gravity of the counterweight 22 is placed in such a position that the maximum eiiiciency of the apparatus can be had. It is of course to be considered that manufacturing conditions make it necessary to limit its position within a certain range but I find it desirable to place it by mathematical computation with reference to the eective crank arm length which in this case is the combined distance of the crank arm length and the length of the locked eccentric. A ratio, of 3 or more between the effective crank arm (A B E) and the distance of the center of gravity from the effective crank pin center E has been found to be especially suitable as it brings about a normally strong centrifugal force for crushing and yet the operating radius, on

the diagram, E C is so small that rapid resultsv are obtained. With a concentric weight the center of gravity of the operating eccentric would be at C although with a horseshoe shape weight as shown, the center of gravity-of the operating eccentric is at a point slightly beyond the center of the operating eccentric from the crank pin.

In the diagram, both eccentrics are shown to have substantially equal eccentricitles but this is not necessary. The shorter the link of the operating eccentric the shorter radius its center of 'gravity will tend to move on in cas of abnormal operation and therefore the quicker the `eccentrics will move intoA collapsed position. The only limitation as to size is a practical one although the combined eccentricity of the two eccentrics preferably pro'vides for movement of the muller shaft to a concentric position with the drive shaft.

It will be seen that with a structure, there4 is a maximum ratio between the length of the crank arm and the distance between the center of gravity of the eccentric and the center of the crank pin. The efficiency of operation thereby becomes a maximum.

The operating eccentric 20 may be constructed so that its median line is in line with the center of gravity line through the Vcenter of the crank socket, or it may be in advance of or lag behind this center line. By the preferred construction, the median line of the operating eccentric lags behind the center of gravity line approximately 50, see Fig. 2.

Under normal operating conditions, the muller shaft 30 carries the muller in crushing relation to the crusher jaws. This is a position of very little clearance with lthe result that a hard and uncrushable particle will reacton the respectiveeccentrics in such a manner that the muller shaft may be made concentric with the drive shaft as shown in Fig. 8. After the obstruction in the crusher has been removed the .locking member 49 can be released by projecting a suitable tool through the casing 43 or mechanical means can 50 shown'in Fig. 1 I'he worm is operated by a.`

suitable crank 5I or by any other desired means and in turn will rotate the worm gear 52 which is keyed to the lower half of the bearing 33. This in turn is provided with a screw thread and in rotation will. force the entire bearing 38 in a vertical manner to control the proximity of the muller 32 to the crusher jaws 34.

This adjustment can be made when the crusher is running to obtain the desired fneness with- 5 out the necessity of closing down the crusher as was formerly necessary. Furthermore, as the crushing surfaces wear, a slight turn of the worm will maintain the same relative'position of the for oil which returns to the cooler 56 through the 20 l intake pipe 51. Oil is also drawn from the roller bearings I9 through the pipe 58 and lfrom the upper bearing 38 through pipe 59. After being' suitably cooled in the cooler'56, it is pumped from the pump so initially into the chamber si from 25 which point part of the lubricant flows through the muller shaft 30 into the lower bearing and the other part lubricates the upper bearing as needed. The pump may be driven by any suitable means (not shown.) 30

A modified form of construction of eccentric is diagrammatically shown in Figs. 1l and 12 in which a single eccentric 65 is mounted on the crank pin 66 of the crank 61. AIn this construction, the eccentric is provided with counterweights 69 35 with the center of gravity line passing the'axis approximately at the point 69. It will be seenthat by suitable counterweights this center of gravity can be placed at such a point so that its distance from the crank pin 66 is a fraction of the length of the crank arm. This ratio of crank arm length to effective operating radius of the center of gravity can be three or more as in the previous case with similar beneficial results.

The drawings are intended to illustrate the principle of drive linkage which is effective in giving adequate crushing power and yet permit the operation of the floating eccentric when an uncrushable particle is encountered. The precise details of size and parts however, depends on the type of crushing and materials crushed. Other modifications canv also be made in arrangement of parts and the invention is therefore not to be considered as limited to any particular size or shape of parts but is to be given a broad interpretation within the scope and spirit of the descrip,-

tion herein and of the inafter.

I claim-z `claims appended here- 1. A gyratory emsher of the class described so having a fixed crusher jaw and a gyratory muller corresponding therewith, amuller shaft carrying said n'iuller and means to rotate one endof'the muller shaft, including a crank, a floating eccentriccarried by the crank pin of said crank, and ,65 a bearing for said muller shaft on said eccentric, said eccentric having a center of gravity at such a distance from the crank pin center that the radius of rotation of the eccentric about the crank pin center is substantially smaller than the length 70 of the crank, said eccentric being adapted to move the muller shaft center intosubstantial coincidence with the' crank center 'if an obstruction is encountered at the crusher jaws. v

2. A drive linkage for rotating .a muller man is about a crank center for gyrating motion of a muller carried on said shaft which comprises a crank mechanism having an effective crank piu center, a floating eccentric carried at the effective crank pin center, said eccentric having a bearing for one end of the mullershaft, a weight on said floating eccentric, the centrifugal force of which tends to maintain the radius of rotation of said muller shaft, the center of gravity of said weight being so placed with respect to the crank pin center that it has a radius of rotation about said effective crank pin center if an obstacle is encountered that is short as compared to the effective crank arm length. said eccentric with a center of gravity at a distance from the eective crank pin center which is relatively small as compared to the length of the effective crank arm, whereby the initial movement of the operating eccentric will be on a short arc.

4. A gyratory crusher of the class described having a fixed crusher jawand a gyratory muller cooperating therewith, a muller shaft carrying said muller and means to rotate one end of the muller shaft, including a crank, a floating eccentric carried by the crank pin `of said crank and a bearing for said muller shaft on said eccentric, said eccentric having a center of gravity at such a distance from the crank pin center that the radius of rotation of said center of gravity about the crank pin center is of the order of one third the length of the crank, said eccentric being adapted to move the muller shaft center into substantial coincidence with the crank center if an obstruction is encountered at the crusher jaws.

5.' A gyratory crusher having a casing, a crush- `er jaw, a muller shaft with a muller adjacent said .auxiliary eccentric from said crank' socketwhen said operating eccentric is moved through a pre-determined angle.

6. A gyratory crusher of the class described having a fixed crusher jaw and a gyratory muller cooperating therewith, a muller shaft carrying said muller and means to rotateone end of the muller shaft, including -a crank, a floating eccentric carried -by the crank pin of said crank and a bearing for said muller shaft on said eccentric, said eccentric having a center of gravity at such a distance from the crank pin center that. 'its radius` of rotation about the :crank pin center is substantially smaller than the lengthV of the crank, said eccentric being adapted to move the muller shaft center -into substantiaicoincidence with the crank center if an obstruction is eny countered at the crusher jaws, and means to lock the eccentric in concentric position.v

'7. In a gyratory crusher, a crusher member, a muller shaft having a muller adjacent said crushing member, and means to gyrate said muller in crushing relation'with said crusher member, said means including ay driven crank and a plurality of eccentrics, one of said eccentrics having a bearing for one end of said muller shaft, Vlocking means to normally lock the crank and one eccentric together and means carried by the other eccentric to unlock the eccentric and crank and to lock the two eccentrics together when an obstacle is engaged at the crusher member, the eccentricity of the locked eccentrics being such that the gyrating end of the muller shaft will move to a position concentric with the other end.

8. A gyratory crusher of the class described having a fixed crusher jaw and a gyratory muller cooperating therewith, a muller` shaft carrying said muller and means to rotate one end of the muller shaft, including a crank, a floating eccentric carried by the crank pin of said crank and a bearing for the gyratory end of said muller is substantially smaller than the length of the crank, said eccentric being adapted to move the muller shaft center into substantial coincidence with the crank center if an obstruction is encountered at the crusher jaws, said eccentric havinga center of gravity on a line through the center which is at a leading angle with respect to a median line through the center of the crank pin and the center of -the eccentric.

9. A gyratory crusher ofy the class described having a fixed crusher jaw and a gyratory muller cooperating therewith, a muller shaft carrying said muller and means to rotate one end of the muller shaft, including a crank, a floating eccentric carried by the crank pin of said crank and a bearing for said muller shaft on said eccentric, said eccentric having a center of gravity at a distance from the crank pin center such that the radius of rotation of the center of gravity about the crank pin center is of the order of one third the length of the crank or less, the center of gravity of said eccentric being on a line through the center'which yis at a leading angle with respect to a median line, said eccentric being adapted to move the muller shaft center into substantial coincidence with the crank center if an obstruction is encountered at the crusher jaw,

and means to lock the eccentric in concentricI position.

10.v In a crusher having a stationary crusher member anda movable crusher member cooperating therewith, means for moving the movable crusher member to and from the stationary crusherr member including a crank having a crank pin and a floating eccentric, said floating eccen-l tric being freely rotatable about said crank pin, said oating eccentric having a counterweight so positioned with respect to the crank pin that the length of theA crank is at least three times other end of said muller shaft, means to move said muller shaft to a concentric position, means to hold said muller shaft in said cencentric position and means to move said muller shaft with respect to said crusher jaws to vary the neness of grind, said movable means including an adjustable bearing for the relatively fixed point bearing and means to adjust it during operation of the muller.

moved.

13. In a gyratory crusher having a casing, a muller shaft having a muller thereon, said casing having crusher jaws adjacent said muller,

.an upper semi-spherical shaped bearing for said muller shaft, and a lower crank pin socket for gyrating said muller shaft, centrifugal means to move said muller shaft to a concentric position on contact with an uncrushable substance and a releasable linkage to hold said muller shaft in said concentric position, said linkage being man ually releasable after the uncrushable substance is removed so that the muller shaft may regain its eccentric position` 14. In a gyratory crusher having a casing. a

muller shaft havinga muller thereon, said casing having crusher jaws adjacent said muller, an upper semi-spherical shaped bearing for said muller shaft, and a lower crank pin socket for gyrating said muller shaft, means to move said' muller shaft to a concentric position, means to positively hold said muller shaft in-concentric position if it moves to such position and means to lubricate said upper bearing and said lower socket and said muller shaft means, said lubricating means including a pressure oil pump and a cooling device.

15. A gyratory crusher of the class described, having a fixed crusher jaw and a gyratory muller cooperating therewith, a muller shaft carrying said muller and means to rotate one iend of the muller shaft, said means including a crank, an auxiliary eccentric mounted on said crank and forming an eiective crank arm, a floating ecn centric mounted at the end of the effective crank arm, and having a bearing for the end of the muller shaft, said floating eccentric having a'. counterweight, the center of gravity of the oating eccentric being spaced from the end of the eective crank arm a distance which is relatively short when compared to the length of the effective crank arm so that the Aoating eccentric will'move on a short radius if an uncrushable obstacle is encountered in the crushing jaws, lsaid floating eccentric being adapted to carry the muller shaft into a position substantially concentric with the crank for non-crushing operation.

JASPER A. MCCASKELL. 

